The present invention relates to a flow controller and, more particularly, to a flow control washer.
Several different applications exist for washer-type flow controllers. Particularly, in the automotive industry, especially in heating systems, it is desirable to enable fluid to flow as rapidly as possible through a conduit or heater core until a desired flow rate is achieved. Once the desired flow rate is achieved, the flow rate should be maintained at the desired level as pressure increases.
In automotive heating systems where fluids such as antifreeze, glycol or the like are used, it is important to have a rapid flow rate through the system at relatively low pressures. A rapid flow rate at low pressure enables fluid to pass through the heating system to "heat up" faster and, thus, enable warm air to be released into the vehicle passenger compartment.
To accomplish relatively high flow rates at relative low pressure, since the controller itself is a restriction in the conduit, a washer controller must enable maximum fluid flow passage through the conduit. As the pressure of the fluid in the conduit increases, the flow rate through the conduit increases. The washer controller enables the flow rate to increase at a desired rate until the desired flow rate is achieved then the controller maintains the flow rate at the desired level as the pressure in the conduit continues to increase.
Relevant art devices that are utilized in flow control like those illustrated in the following patents. The patents are as follows: U.S. Pat. No. 2,454,929, Nov. 30, 1948 to Kempton; U.S. Pat. No. 2,667,900, Feb. 2, 1954 to Cantalupo; U.S. Pat. No. 2,716,427, Aug. 30, 1955 to Cantalupo; U.S. Pat. No. 2,728,355, Dec. 27, 1955 to Dahl; U.S. Pat. No. 2,775,984, Jan. 1, 1957 to Dahl; U.S. Pat. No. 2,878,836, Mar. 24, 1959 to Binks; U.S. Pat. No. 2,891,578, June 23, 1959 to Dahl et al.; U.S. Pat. No. 2,899,979, Aug. 18, 1959 to Dahl et al.; U.S. Pat. No. 2,936,790, May 17, 1960 to Dahl et al.; U.S. Pat. 2,948,300, Aug. 9, 1960 to Fraser; U.S. Pat. No. 3,141,477, July 21, 1964 to Campbell et al.; U.S. Pat. No. 3,474,831, Oct. 28, 1969 to Noakes; U.S. Pat. No. 4,508,144, Apr. 2, 1985 to Bernett; U.S. Pat. No. 4,609,014, Sept. 2, 1986 to Jurjevic et al.; Re. No. 24,534, Sept. 16, 1958 to Dahl.
While the above patents may perform satisfactorily for their intended purpose, designers strive to improve the art. Thus, the present invention provides the art with a washer-type control device which enables maximum flow at low pressures and a constant desired flow as pressure continues to increase.
From the subsequent detailed description taken in conjunction with the accompanying drawings, other objects and advantages of the present invention will become apparent to those skilled in the art.